Brush for applying a make-up product, particularly mascara

ABSTRACT

A brush for applying make-up, particularly mascara, including a shaft provided at one end with a core (6) formed by two metal wires (7, 8) twisted together and having bristles (9) squeezed therebetween such that they extend transversely to the core axis. At least some of the brush bristles (9) have an L-shaped cross-section so that the portion of each bristle (9) which is squeezed between said twisted core wires is flattened either outwards when the arms of the L are pushed apart, or inwards when they are pressed together. In either case, the stiffness of the bristle is reduced and the spacing between the bristle and a wire helix formed after twisting is advantageously increased, whereby a random distribution of bristle cross-sections is achieved.

FIELD OF THE INVENTION

The invention relates to a brush for applying a make-up product,particularly mascara, of that type which comprises a wand equipped atone end with a core formed by two branches made from metal wire whichare twisted into turns between which bristles extending transverselywith respect to the core are trapped.

BACKGROUND OF THE INVENTION

Such brushes are used, in particular, for applying mascara to theeyelashes or dye to the hair.

FR-A-2,607,373 shows a brush of this type, a variant embodiment of whichincludes bristles having a cruciform cross-section. Four reserves ofmake-up product are thus constituted along each bristle. At the time ofapplication, the reserves of product are progressively emptied and leadto a homogeneous and thick coating of the eyelashes.

Although permitting an improvement in making-up, such a brush has acertain overall hardness which may sometimes lead to irritation of theskin of the eyelids. The symmetry of the transverse section of thebristle, with respect to the center of this section, gives rise tovirtually identical behaviour on the part of all the bristles when theyare squashed in the zone of twisting of the metal core so that the endsof the bristles reproduce the spiral effect created by the twisted core.

U.S. Pat. No. 3,121,040 relates to filaments made from polyolefins whichare used in different types of brush. Various sectional shapes,presented as equivalents, are proposed for improving the resistance ofthe filaments to deformation. Amongst these sectional shapes is aV-shaped section or a substantially L-shaped section, with no otherparticular indication which might lead to this shape being adopted inpreference to the others.

SUMMARY OF THE INVENTION

Above all, the object of the invention is to provide a brush forapplying a make-up product which has great flexibility but is capable ofachieving extremely good coverage by virtue of a significant charge ofproduct taken up. Moreover, it is desirable for the spiral effect to bereduced at the ends of the bristles.

According to the invention, a brush for applying a make-up product,particularly mascara, of the type defined above, is characterized inthat at least a fraction of the bristles of the brush has a transversesection in the shape of an L, which is known per se, so that the zone ofa bristle wedged between the turns of the metal core undergoes aflattening either through the effect of unfolding when the angle betweenthe branches of the L opens or through the effect of folding when theangle between the branches of the L closes, this flattening reducing therigidity of the bristle on the one hand and, on the other hand,preferentially increasing the spacing of the bristle with respect to thehelical ply formed by the turn, thus creating a disorganized arrangementof the section of the bristles. Thus, the angle formed between the axisof the metal core and the bristle is substantially other than 90°.

Preferably, the branches of the transverse section in the shape of an Lof the bristles have the same length. Advantageously, the branches ofthe L together form an angle of approximately 90°.

The span of the transverse section in the shape of an L of a bristle inthe non-deformed state is preferably between 10 one hundredths and 50one hundredths of a millimetre.

The thickness of each branch of the section of a bristle isadvantageously approximately 0.04 mm.

The ends of at least a portion of the bristles may be shredded,particularly by grinding.

The bristles having a transverse section in the shape of an L may bemixed with other types of bristles, for example bristles having asubstantially flat transverse section or bristles of greater hardness.In the latter case, all the bristles having a transverse section in theshape of an L and harder bristles may be subjected to a grindingoperation so as to obtain bristles having a transverse section in theshape of an L in which the ends are located beyond those of the hardbristles made shorter by grinding.

The ends of the bristles having a transverse section in the shape of anL may be exposed to a source of heat so as to present a swelling. Thebristles having a transverse section in the shape of an L may be mixedwith bristles of smaller section, the whole assembly then being exposedto the source of heat, exposure to the heat giving rise to a shorteningof the bristles with a small section which is greater than that of thebristles having a section in the shape of an L in which the ends projectbeyond those of the bristles of smaller section.

The number of bristles in the shape of an L per turn may be small, ofthe order of 7 to 40 bristles per turn.

BRIEF DESCRIPTION OF THE DRAWINGS

Apart from the arrangements set forth above, the invention consists of acertain number of other arrangements which will be discussed in moredetail hereinafter by way of illustrative embodiments described withreference to the appended drawings, these embodiments in no way beinglimiting in character.

FIG. 1 of these drawings is an outside view, with parts cut away, of areservoir of mascara including a brush for applying the product.

FIG. 2 is a transverse section on a larger scale of a bristle for abrush in accordance with the invention.

FIG. 3 is a partial perspective, diagrammatic view on a large scale ofturns of the core during formation with wedging of the bristles betweenthese turns.

FIG. 4 is a transverse section on a large scale of a section, flattenedby wedging between the turns, of a bristle in the shape of an L in whichthe angle between the branches is open.

FIG. 5 is a transverse section on a large scale of the zone of a bristlewedged between the turns which has undergone folding.

FIG. 6 diagrammatically illustrates an operation of grinding and shapinga brush according to the invention.

FIG. 7 shows on a large scale the end of a bristle which has beenground.

FIG. 8 diagrammatically illustrates an exposure of the brush to a sourceof heat.

FIG. 9 is a perspective view on a large scale of the end of a bristlewhich has been exposed to heat.

FIG. 10 is a partial section of a container equipped with a dryer andwith a brush according to the invention.

FIG. 11, finally, is a diagram illustrating removal of a load of productwith a bristle according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1 of the drawing, it is possible to see anapplicator assembly 1 comprising a reservoir 2 which contains a mascaraM of liquid to pasty consistency. The reservoir 2 is surmounted by a cap3 integral with a brush 4 for applying the mascara M, particularly tothe eyelashes.

The brush 4 comprises a wand 5 equipped at its lower end with a core 6formed by two branches 7, 8 made from metal wire which are twisted intoturns between which bristles 9 extending transversely with respect tothe core 6 are trapped.

At least a fraction of the bristles 9 of the brush has a transversesection S (see FIG. 2) in the shape of an L including two branches 10,11 together forming an angle A. The vertex of the angle is rounded.Preferably, the branches 10, 11 of the section have the same length h.The angle A has a value of substantially 90°.

The span D of the transverse section S, that is to say the diagonaldistance between the ends of the branches, is preferably between 10 onehundredths and 50 one hundredths of a millimeter, the limits of this gapbeing inclusive. The thickness e of each branch is advantageously 0.04mm.

In order to manufacture the brush in a conventional manner, the bristles9 are distributed in bunches, arranged transversely, between thebranches 7, 8 which are parallel before being twisted.

During twisting, which is commenced in FIG. 3, a zone of each bristle 9is wedged between the turns of the metal core. In the zone of thebristle which is wedged between these turns, the transverse section Swill be flattened either by opening the angle A as illustrated in FIG.4, to give the section S1, or by closing angle A after a folding, togive the section S2 in FIG. 5.

Although their transverse section S has a square shape, the bristles 9,when they have been gripped by twisting in the turns of the core 6, losetheir rigidity owing to being flattened in the zone where they areclamped in the turns of the core and which zone constitutes their base.In fact, the moments of inertia of the section S1 and of the section S2are lower than the moment of inertia of the starting section in theshape of an L illustrated in FIG. 2. However, the bristle whose sectionis flattened to become S2 has a double thickness and is more rigid thanthe bristle whose section is flattened into S1. Thus, while reducing therigidity of the bristles relative to a bristle having a section in theshape of an L over its entire length, a mixture of flexible bristleshaving a section S1 in the shape of a flattened open V and of lessflexible (or more rigid) bristles obtained by flattening the closed Vinto S2, as a double thickness, is created along the entire length ofthe brush.

By providing a wide span D and a small thickness e, it is possible toobtain a particularly soft brush which prevents any irritation but whichensures very rapid making-up and good coverage, since the bristles 9 areloaded with a large amount of product in the concavity of their section.

The reservoir 2 is equipped, at the top, with a dryer 12 (see FIG. 10)including a reservoir of small diameter which is intended to betraversed by the bristles 9 during removal so as to dry off the excessproduct. As illustrated in FIG. 11, the bristles 9 remain laden withproduct in the zone 13 located inside the section in the shape of an L.Opening of the section of the bristles to approximately 90° ensures thata large amount of product is taken up, in the manner of a shovel, whilststill protecting this load, in the zone 13, against excessive dryingoff.

The bristles 9 are dried off according to the variable orientation oftheir ends, which gives rise to a brush having variable drying-off.

The large load of product on the bristles makes it possible to achieveextremely good coverage while still having a brush with greatflexibility.

When they are clamped between the twisted branches 7, 8 of the core, thebristles 9 preferentially fold according to the diagram in FIG. 4, thatis to say according to an unfolding effect with opening of the anglebetween the branches.

The transverse section in the shape of an L of the bristles isasymmetrical with respect to the vertex of this section so that thedeformations created by clamping between the turns gives a randomdistribution in terms of the orientation of the portions of the bristlesextending from the core. The brush thus produced is tufted and the endsof the bristles distributed randomly (as shown diagrammatically in FIGS.6, 8 and 10) reduce the spiral effect usually created on conventionalmascara brushes by the twisted core.

The core 6 of the brush is not necessarily central and may beoff-center.

The brush 4 may be shaped by a grinder 14 (see FIG. 6) which is, forexample, frustoconical, the axis of which is arranged parallel to thatof the core 6 of the brush. Generally, for the grinding operation, thebrush 4 is made to turn about the axis of the core and of the wand 5 andthe grinder 14 is made to turn about its axis, preferably in a directionopposite to the direction of rotation of the brush. Generally, it ispossible to give the brush 4 the desired shape by using a grinder 14 ofcomplementary shape.

Grinding of the bristles 9 of the brush may also be carried out withoutmodification of the overall shape of the brush 4. Grinding produces tornends on the bristles 9 which have the form of forks 15 (FIG. 7)substantially corresponding to the section of a right-angled dihedronthrough a plane which is inclined with respect to the edge of thedihedron.

It should be noted that the bristles 9 having a transverse section inthe shape of an L may be mixed with bristles of greater hardness. Duringa grinding operation, the bristles 9 having a section in the shape of anL will be worn away less than the harder bristles and, after grinding,the bristles 9 having a section in the shape of an L will have theirends located beyond those of the harder bristles. The harder bristlesmay be cylindrical bristles having a circular section or flat bristlesor bristles having a section in the shape of a horseshoe.

As illustrated in FIG. 8, the brush 4 may be exposed to a source of heat16, for example an infrared radiation array placed substantiallyparallel to a generatrix of the brush 4. Preferably, the brush 4 is madeto turn about its axis in front of this source of heat 16. Thetemperature of the source 16 is chosen so that the ends of the bristles9 begin to melt, giving rise to an inflation 17 in the shape of an L, asmay be seen in FIG. 9, which extends along the entire transverse borderof the bristle.

The bristles 9 having a section in the shape of an L may be mixed withbristles of smaller section and then exposed to the source of heat 16.During heat treatment, the bristles of smaller section, which are lessresistant to the heat, will suffer a reduction in length greater thanthat of the bristles having a section in the shape of an L in which theinflated ends 17 will remain projecting beyond the ends of the bristlesof smaller section.

The bristles having a section in the shape of an L may be mixed withbristles having a flat transverse section, particularly with bristles inwhich the substantially rectangular section has a major dimension whichis at least equal to double the minor dimension and no more than fivetimes as large as this minor dimension, as stipulated in FR-B-2,627,363.

The bristles having a transverse section in the shape of an L arepreferably obtained by extrusion through a suitable die. These bristlesmay be produced from polyamide plastic PA6-66; 6-10; 6-12 or from PA11(commercial name RILSAN), or from polyethylene, from a thermoplasticelastomer such as polyurethane, or from block polyetheramide.

The brushes produced with the bristles having a section in the shape ofan L, according to the invention, may include a small number of bristlesper turn, for example 7 to 40 bristles per turn.

The metal wires, in particularly the iron wires, which are used forbranches 7, 8 of the core may be very fine, with a diameteradvantageously between 5 tenths and 10 tenths of a millimeter, since thebristles 9 having a transverse section in the shape of an L are squashedbetween the turns.

I claim:
 1. Brush for applying a make-up product, comprising a wandequipped at one end with a core formed by two branches made from metalwire which are twisted into turns between which bristles extendingtransversely with respect to the core are trapped, wherein at least afraction of the bristles of the brush has a transverse section in theshape of an L so that a zone of a bristle wedged between the turns ofthe core undergoes a flattening by the effect of one of unfolding whenan angle between the branches of the L opens, and folding when the anglebetween the branches of the L closes, said flattening reducing therigidity of the bristle and increasing the spacing between the bristleand a helical ply formed after twisting, thereby creating a disorganizedarrangement of the section of the bristles, said bristles having atransverse section in the shape of an L being mixed with harder bristlesso as to form an assembly, and said assembly being ground in order toobtain bristles having a transverse section in the shape of an L andwhose ends are located beyond those of the harder bristles made shorterby grinding.
 2. Brush for applying a make-up product, comprising a wandequipped at one end with a core formed by two branches made from metalwire which are twisted into turns between which bristles extendingtransversely with respect to the core are trapped, wherein at least afraction of the bristles of the brush has a transverse section in theshape of an L so that a zone of a bristle wedged between the turns ofthe core undergoes a flattening by the effect of one of unfolding whenan angle between the branches of the L opens, and folding when the anglebetween the branches of the L closes, said flattening reducing therigidity of the bristle and increasing the spacing between the bristleand a helical ply formed after twisting, thereby creating a disorganizedarrangement of the section of the bristles, said bristles having atransverse section in the shape of an L being mixed with bristles ofsmaller section so as to form an assembly, said assembly then beingexposed to a source of heat, exposure to the heat giving rise to ashortening of the bristles of the shorter section, which is greater thanthat of the bristles having a section in the shape of an L, whose endsproject beyond those of the bristles of smaller section.